OMs, or OTs), respectively. 6β-Phthalimidopenicillanoyl-methane and -methyl iodide (6; X = H or l) are formed in the reactions of compound (5) with hydriodic acid and iodine, respectively. The derivatives (6; X = leaving group) undergo tertiary-amine-induced ring expansions to give mixtures of 4-isopropylidene-3-oxo-7β- and -7α-phthalimidocephams [(19) and (20)]; the ratio (19) : (20) is sensitive
6β-Phthalimidopenicillanoyldiazomethane(5)反应,用
盐酸,
甲磺酸,和
甲苯p -sulphonic
硼酸开始,得到6β-phthalimidopenicillanoylmethyl
氯化物,
甲磺酸盐,
甲苯和p -
磺酸盐(6; X =
氯,OMs的,或O
TS),分别。在化合物(5)与
氢碘酸和
碘的反应中分别形成6β-邻苯二甲酰胺基半
乳糖醛基
甲烷和-甲基
碘(6; X = H或l)。衍
生物(6; X =离去基团)经历叔胺诱导的环扩展,得到4-异亚丙基-3-氧代-7β-和-7α-邻苯二甲doc [[19]和(20)]的混合物。(19):(20)的比例对离去基团,碱和溶剂敏感。化合物(6; X = Cl)的3-质子的抽象表示重排中的缓慢步骤。